1. Field of the Invention
The present invention relates generally to fasteners for securing panel-like members together, and, more particularly, it relates to a grommet into which a push-pin may be inserted. The grommet may, for example, be inserted and retained in a fitting hole in a supporting panel, such as a metal door panel of an automobile vehicle, and thereafter to receive the push-pin for mounting a mating panel having a through-hole, such as a decorative lining panel, to the door panel. The grommet is adapted to absorb variations in the relative positions of the supporting panel and the mating panel caused by thermal expansion and contraction due to temperature changes. The grommet is molded in an open condition, and folded to assume an encapsulating condition when it is to be used.
2. Description of the Prior Art
Grommets designed for use in the above-mentioned environment are known in the art.
For example, U.S. Pat. No. 3,830,134 to Erickson shows a one-piece plastic anchor for accommodating a cylindrical expander element, such as a screw threaded fastener, in fixed relation to an apertured workpiece. The anchor member includes an apertured clamping head and a shank section which has a pair of spaced leg members and an oval tubular member spaced from and located between said legs in communication with the head aperture to accommodate the expander element for the purpose of distorting the oval tubular member into engagement with the medial surfaces of said legs to lock the anchor in the workpiece aperture.
U.S. Pat. No. 4,284,378 to Mizusawa shows a fastener for panels, comprising a basal body provided with a flange portion having a circular perforation bored in the central portion thereof for permitting insertion therethrough of a screw, and having a pair of legs extended downwardly from the lower surface of the flange portion so as to be opposed to each other across the line drawn perpendicularly through the center of the circular perforation, and a screw-receiving body disposed between the opposed legs, provided in the upper portion thereof with a pair of receiving pieces protruding sideways out of the openings formed between the opposed legs and further provided with a screw-receiving hole in the axial portion coinciding with the perpendicular line drawn through the center of the perforation. The screw-receiving body is provided with engaging protuberances one each on the lateral surfaces thereof opposite the legs and the legs are provided with oblong-guide holes adapted to receive the engaging protuberances. The work of setting the engaging protuberances into sliding engagement with the oblong guide holes and tightening a screw inserted past the perforation of the flange portion into the screw-receiving hole of the screw-receiving body causes the receiving pieces of the screw-receiving body to be slid in the direction of the flange portion of the basal body and thereby enables a panel to be held fast between the flange portion and the receiving pieces or panels one each between the head of the screw and the flange portion and between the flange portion and the receiving pieces.
British Patent No. 1,309,392 shows an expandable bolt anchoring device suitable for fixing in a hole prepared in brickwork, masonry, concrete or the like comprising a cylindrical shell adapted to be expanded in the hole by means of a tapered nut expansion member which is displaceable within and along the shell, and a bolt having a shank engageable in and through the expansion member, wherein the shell comprises two or more longitudinal segments which can be placed in a confronting relationship to define the shell of which the bore is partially closed at one end by a wall, or entirely closed at said one end by a frangible wall, and open at the other end, the bore being enlarged adjacent the said one end to form a recess which accommodates the expansion member in the unexpanded condition of the shell and which converges towards the open end, the construction being such that, after the shank of the bolt has been turned into the expansion member and through it until it bears on said wall, continued turning of the bolt will displace the expansion member along the shell towards said open end to force the shell segments apart, whereafter any further turning of the bolt is effective to force its shank through the partially closed or frangible wall.
U.S. Pat. No. 4,407,618 to Kimura shows a fastener which comprises a base formed of a flange and a plurality of leg pieces and a screw-receiving member adapted to be embraced between the leg pieces, whereby it is secured onto a given panel by a procedure which involves inserting the leg pieces into a fitting hole bored in advance in the panel, then inserting a fastening screw through a through hole formed in the flange into a screw hole formed within the screw-receiving member, imparting a helical motion of the fastening screw thereby drawing the screw-receiving member toward the flange, consequently causing the leg pieces to be spread outwardly within the fitting hole of the panel and brought into tight engagement with the fitting hole and, at the same time, enabling the fastening screw to be secured onto the panel through the medium of the base.
U.S. Pat. No. 5,028,190 to Loughlin, Jr. et al. shows a one-piece screw anchor adapted for snap-in capture in a substructure elongated rectangular aperture enabling it to slide along the aperture major axis. Upon the insertion of a self-tapping screw in a panel circular opening overlying the screw anchor, the screw tip enters the anchor upper lead-in chamber. If the screw and anchor are misaligned, the screw tip contacts a subjacent one of a pair of opposed anchor ramped side surface portions whereby the anchor is crammed for limited adjustment along the aperture major axis. The anchor ramped surface portions terminate in a lower, elongated channel extending transverse to the major axis. The anchor base wall is adapted to be threadably engaged upon driving the screw at a piercing point in a vertical alignment with the panel opening.
U.S. Pat. No. 5,129,768 to Hoyle et al. shows a sliding grommet including a head flange and a shank portion of a unique construction which is capable of absorbing relative positions of an oblong fitting hole in a mounting panel and a through hole in a mating hole to be attached caused by thermal expansion and contraction. A pair of Y-shaped members are disposed on opposite sides of the shank portion to permit flexing upon insertion, and locking tabs are provided on each leg of the Y-shaped members for retaining freely floating the shank portion in the oblong fitting hole in the mounting panel so as to permit lateral sliding engagement between the upper and lower edges of the fitting hole.
U.S. Pat. No. 5,193,961 to Hoyle et al. shows a pin and grommet assembly including a push-pin and a grommet of unique construction capable of absorbing variations in the relative positions of a supporting panel and a mating panel to be attached caused by thermal expansion and contraction. A pair of diametrically opposed semicylindrical-shaped portions are disposed on the push-pin and cylindrical-shaped mating grooves are formed in the interior of the grommet for retaining freely floating the semicylindrical shaped portions in the grommet so as to permit lateral sliding engagement between the opposed outer wall surfaces on the shorter sides of the main body portion of the grommet.